Internet of Things (IoT) has facilitated integration of wireless communication capabilities into sensing devices. IoT enables monitoring of many electrical, physical and environmental parameters. Electrical power consumption is one of such important parameters to be monitored. In literature, many power monitoring devices have been proposed for this purpose. But they are expensive, complex and lack adequate security measures. We have addressed these problems by proposing an implementation of a simple, compact, low-cost and secure power monitoring sensor with WiFi capability. Various results are presented to show the feasibility of the proposed power monitor sensor for measurement and secure transmission of data. © 2017 IEEE.